Estimation of thoron concentration using scintillation cell.

Two counting techniques are proposed in this paper to estimate thoron ((220)Rn) concentration using a Lucas scintillation cell. The alpha activity build-up inside the cell is calculated theoretically by using Bateman equations. The first method is having a minimum detection limit of 325 Bq m(-3) and can be used for thoron measurement in thorium-processing plants. In the second method, thoron concentration is calculated using the alpha counts from thoron progenies and is a reference to the first method. The results obtained by these techniques compare well with the double filter method.